Direct grafting of tetraaniline via perfluorophenylazide photochemistry to create antifouling, low bio-adhesion surfaces

• Published in: Chemical science (Cambridge) 2019-04, Vol.10 (16), p.4445-4457
• Main Authors: Lin, Cheng-Wei, Aguilar, Stephanie, Rao, Ethan, Mak, Wai H, Huang, Xinwei, He, Na, Chen, Dayong, Jun, Dukwoo, Curson, Paige A, McVerry, Brian T, Hoek, Eric M V, Huang, Shu-Chuan, Kaner, Richard B
• Format: Article
• Language: English
• Subjects: Biofouling; Biomedical materials; Carbon nanotubes; Chemical treatment; Chemistry; Corrosion prevention; Cross flow; Dip coatings; E coli; Grafting; Graphene; Hydrophilicity; Immersion coating; Ionization; Membranes; NMR; Nondestructive testing; Nuclear magnetic resonance; Organic chemistry; Photochemistry; Polyanilines; Polyethersulfones; Polyethylene terephthalate; Serum albumin; Transmission electron microscopy; Ultrafiltration; Water purification
• ISSN: 2041-6520; 2041-6539
• DOI: 10.1039/c8sc04832k

Conjugated polyaniline has shown anticorrosive, hydrophilic, antibacterial, pH-responsive, and pseudocapacitive properties making it of interest in many fields. However, grafting of polyaniline without harsh chemical treatments is challenging. In this study, we report a simple, fast, and non-destructive surface modification method for grafting tetraaniline (TANI), the smallest conjugated repeat unit of polyaniline, onto several materials perfluorophenylazide photochemistry. The new materials are characterized by nuclear magnetic resonance (NMR) and electrospray ionization (ESI) mass spectroscopy. TANI is shown to be covalently bonded to important carbon materials including graphite, carbon nanotubes (CNTs), and reduced graphene oxide (rGO), as confirmed by transmission electron microscopy (TEM). Furthermore, large area modifications on polyethylene terephthalate (PET) films through dip-coating or spray-coating demonstrate the potential applicability in biomedical applications where high transparency, patternability, and low bio-adhesion are needed. Another important application is preventing biofouling in membranes for water purification. Here we report the first oligoaniline grafted water filtration membranes by modifying commercially available polyethersulfone (PES) ultrafiltration (UF) membranes. The modified membranes are hydrophilic as demonstrated by captive bubble experiments and exhibit extraordinarily low bovine serum albumin (BSA) and adhesions. Superior membrane performance in terms of flux, BSA rejection and flux recovery after biofouling are demonstrated using a cross-flow system and dead-end cells, showing excellent fouling resistance produced by the modification.